Diaphragm-actuated horn and resonator therefor.



M. R. HUTGHISON DIAPHRAGM AOTUATBD HORN AND RESONATOR THEREFOR.

APPLICATION FILED MAY 6, 1909.

Patented May 3, 1910.

MS ATTORNEY n" W MM WITNESSES.-

Mlum! a, 671mm :0. Psm'o-umocmmiis. WASHINGTON n. c.

MILLER REESE HUTGl-IISON, OF SUMMIT, NENV JERSEY.

DIAPHRACfiM-ACTUATED HORN AND RESONATOR. THEREFOR.

Original application filed May 16, 1907, Serial No. 378,946.

Specification of Letters Patent.

Patented May 3, 1910.

Divided and this application filed May 6, 1909.

erial No. 48%,395.

T 0 (LR whom it may concern:

Be it known that I, MILLER Rnnsn HU'I'OHISON, a citizen of the UnitedStates, and a resident of Summit, in the county of Union and State ofNew Jersey, have invented certain new and useful Improvements inDiaphragin-Actuated Horns and Resonators Therefor, of which thefollowing is a specification.

My invention concerns improvements applicable to diaphragm-actuatedhorns, such as shown in my applications Serial Nos. 278,562, 280,910 and291,518, and in my Patents 923,0 l8, 923,0 l9 and 923,122, of May 25,1909, and particularly those disclosed in the said patents, this casebeing a division of my application Serial No. 37 5,9410, on which saidPatent No. 923,0%0 was granted.

The invention has for its object to im prove the construction andrelative arrangement of supporting bracket, diaphragm case, andresonator or horn proper. The latter is preferably flattened andpreferably pro vided with an oval or laterally flattened bell mouth. Itis preferably secured to the front wall of the case by means of aforwardly extending flange, to which it may be socured by brazing orspinning, or both. The case is arranged to clamp the periphery of thediaphragm and to form a more or extended annular space or cavity infront of the diaphragm and surrounding the open ing for the horn, thisspace being preferably relatively narrow and the front wall beingpreferably parallel with the diaphragm. Openings or passages arepreferably provided in the front wall of the casing adjacent the bottomof such space or cavity, thus affording an outlet for dirt, water, etc,which may enter through the open end of the horn.

hen the device is not in operation foreign matter may drain out or maybe shaken out of the opening and when the diaphragm is vibrated thepuffs of air will also tend to clear out any accumulation of matter notremoved by ordinary drainage. This feature is a great improvement and isof especial advantage in connection with any apparatus having avibratory acoustic diaphragm intended for use in exposed situations,inasmuch as the cavity on the front face of the diaphragm is relieved offoreign matter entering from the outside while the space in the rearpart of the case is closed in by the diaphragm itself, so that thecooperative parts or actuating devices whose functions are correlatedwith the vibrations .of the diaphragm, are perfectly protected withoutin any manner interfering with the intimate coiiperative relation.

The various features are preferably embodied in a unitary arrangementcomprising a laterally flattened horn, a laterally projecting bracketfor supporting the horn, holes at both top and. bottom of the front wallof the case for the exit of foreign matter, and provision for reversingthe power connections of the horn at the rear of the case, so that ahorn provided with a single lateral bracket may be secured on either theright or the left hand side of a support.

hfy invention will be more fully understood from the accompanyingdescription and the claims when considered in connection with theaccompanying drawings, in which- Figure l is a side elevation of theinstrument with the diaphragm and adjacent parts broken away to verticalsection; Fig. 2 is a face view looking into the resonator, showing theinstrument attached to the side of a suitable support.

Fig. 1 shows certain characteristic features of the operating mechanismof the horn sufficient for present purposes. It will be understood thatthe details now shown may be and preferably are such as shown in saidapplication Serial No. 373,046 (Patent h'o. 923,0QQ). The operatingmechanism comprises a cam l, suitably supported in operative relation toa thrust member 2, secured upon the steel diaphragm 3. The structure ofthe latter may be such as described in my Patent No. 883,645. The cam isrotated by flexible shaft t passing through the boss 5 in the case 25,and secured in place by a nut 0. The case is formed with similar boss 7in which an oil cup 8 secured by nut The bosses 5 and 7 are similar andsymmetrical, so that either one of them is equally adapted for passageof the drive shaft or of the oil cup, according as the device isarranged one side up or the other side up in practical use.

The rear section of the case is formed with an annular clamping surface10, adapted to cooperate with the front case or resonator section 11, toclamp the peripheral portion of the diaphragm 3. The front wall of thecase is preferably parallel with the diaphragm and spaced far enoughaway from it to permit maximum vibration of the dia phragm withoutengagement of the latter with the case thereby forming a chamber back ofthe resonator section 11 which serves at once as an air chamberacoustically aiding in the operation of the horn and as a chamber forthe reception of foreign matter such as moisture, sand, dirt, etc. The

, case is formed with a central opening 15 preferably of large diameterso as to expose a large part of the effectively vibrating part of thediaphragm, preferably onethird to two-thirds of the entire unclampedarea thereof. The size of this opening determines the size of the baseor smaller end of the resonator which fits over it. The walls of theresonator diverge but slightly over most of the length of its bodyportion, so that exclusive of the bell mouth, the air column is shortand thick and of relatively uniform cross-sectional areas, as comparedwith ordinary horns. This gives a heavy resonant air column, welladapted to transmit as a definite acoustic wave the large amount ofpower available from the mechanically driven diaphragm.

As explained in my original application, now Patent No. 923,049, ofwhich this case is a division, the resonator with its resonant aircolumn is excited by the diaphragm and vibrating means, preferably so asto produce a definite note of frequency corresponding to or lower thanone of the natural frequencies of the device and such frequencies may berelatively low, that is of the order of four or five hundred per secondbut not too low to give a definite note.

The opening 15 is surrounded by an annular flange let. The resonator 13is secured to this flange either by spinning the metal against the outerwall thereof or by brazing, or preferably by both. The pe riphery of thefront case 11 is preferably formed with a rearwardly extending annularflange 16 adapted to fit over the rear section of the case and protectthe seams between the diaphragm and clamping surfaces.

The quality of the note is improved and destructive vibration andcutting action of the diaphragm, which would result from direct contactof vibratory elastic metals, is prevented by washers or gaskets 12, 12,arranged on each side of the diaphragm between it and the clamping faceson the front and rear sections of the case. These washers may be ofnon-vibratory material, such as cork, wood, or hardened fiber, thematerial and the arrangement thereof being such that when clamped inplace by the screw bolts 12 a water tight joint is formed. This featuredoes not form part of the subject matter of this application the claimstherefor having been canceled for transfer to another application.

As the open end of the horn is usually presented in the direction ofmovement of the vehicle or launch, it is desirable to have exit openingsat 19, 20, so as to afford an outlet for water or small particles ofsand or dirt, which may find their way through the open end of the horninto the space between the diaphragm and the front wall of 11. Asstated, this space is preferably not much wider than is necessary topermit maximum vibration of the diaphragm without its striking againstthe case both for acoustic reasons and to promote discharge of foreignmatter, though this depends largely upon the relative proportions of theparts and good effects may be secured with wider spaclng. By having twosuch exits for foreign matter, one at the top and the other at thebottom of the case, there will always be one of them in operativeposition, whichever side of the device happens to be downward when inuse. The device is provided with a bracket 22, adapted to be secured bybolts 23 to the side of an upright support 24, which in this case isshown as a section of the dashboard of an automobile.

As will be evident by comparing Figs. 1 and 2, the resonator 13 islaterally flattened so as to have a transverse major axis arrangedvertically and preferably terminating in a bell, having acorrespondingly flattened or oval outline.

\Vhere the sound produced is a definite note of definite frequency,where the frequency is such that the physical length of each half waveof sound, 1s greater than the length of the resonator, and where thereis resonance of the air column of the horn, flattening of the resonatorhas the effect of spreading the sound in the direction in which theresonator is of smaller dimension and of limiting the spread in thedirection in which the resonator is of greater dimension. Thisphenomenon renders the device particularly convenient for attachment tothe side of a support, since the disposition of resonator which is mostadvantageous acoustically, is also the one which is most compact andmost desirable physically.

It will be obvious from the above that if it is desired to shift thehorn from the side of the dash-board indicated in Fig. 2 over to theother side, it is only necessary to reverse the connection of theflexible shaft 4 and oil cup 8, and to turn the horn over so that thebracket 22 will project from the left hand side thereof, instead of theri ht hand side. In either case, the resonator as its major axis in avertical plane with the one or the other of the drain holes in positionto afford an outlet from whichever portion of the space between thediaphragm and front wall happens to be lowermost.

The special acoustic features and advantages resulting from proximityand parallelism of the front wall of the case to the diaphragm, from therelatively great internal diameter of the sound opening and the base ofthe horn as compared with the diameter of the diaphragm, and from thelateral flattening and vertical flaring of the resonator, are each ofspecial significance and all cooperate effectively for the abovedescribed purposes when the diaphragm vibration consists of a bodilymovement of all of the central portions of the diaphragm simultaneouslyin the same direction, or when the diaphragm vibrations are forcedregularly so as to produce definite notes or when the frequency of thenote is the same as that of the resonator. The drainage or clearingoutarrangements for the space in front of the diaphragm prevent thesefeatures and advantages from becoming inefiectual when the device isused in exposed situations. The drainage openings or exit passages ororifices, as 1 have variously termed them, are particularly efficient byreason of the proximity thereto of the vibratory diaphragm and where thevibrations of the latter are of considerable amplitude so as to producedelinite unitary waves of condensation and rarefication, the recurrenthigh velocity air movements caused thereby are peculiarly eliicient inagitating and clearing out anything that may find its way into the spacebetween the diaphragm and the wall of the case.

While I have herein fully shown and described, and have pointed out inthe appended claims certain novel features of construction, arrangement,and operation which characterize my invention, it will be understood bythose lllQCl in the art that various omissions, substitutions, andchanges in the forms, proportions, sizes and details of the device andof its operation, may be made without departing from my invention.

1 claim:

1. A signal device comprising a vibratory diaphragm, and means forapplying power for forcibly vibrating the central portions thereof toproduce a definite note of definite normally uniform frequency, incombination with a casing member having an annular wall, and a straightresonator rigidly secured over the opening through said wall with itslongitudinal at right angles to the plane of the diaphragm and with itsopening end parallel thereto. said annular wall being arranged close tobut normally out of contact with the central or vibr: ting portions ofthe diaphragm and forn'iing therewith a thin annular space, theclearance between the diaphragm and easing at points adjacent thecentral opening being only slightly greater than the maximum amplitude.of the diaphra m vibrations, said opening having an internal diametermore than one-third the diameter of the vibrating portion of thediaphragm, the body portion of said resonator being formed with slightlydiverging walls and being relatively short and thick proportionally tothe diameter of said opening; together with means for securing saiddevice with the longitudinal axis of said resonator approximatelyhorizontal, for the purpose described.

A signal device comprising a vibratory diaphragm, means for applyingpower for forcibly vibrating the diaphragm so as to produce a definitenote of definite normally uniform frequency, and a casing for the frontof the diaphragm having a front wall forming a space in front of thediaphragm and provided with an opening for the sound waves, incombination with a horn or resonator secured around said opening, theresonator being formed toward its open end with a laterally flattenedportion having an approximately straight longitudinal axis andterminating in a bell mouth having its lateral diameter less than itsvertical diameter and means for securing the device with the saidstraight axis approximately parallel to the ground and with the greaterdiameter thereof approximately perpendicular to the ground, for thepurpose described.

A signal device comprising a vibratory diaphragm, a rear casing and afront casing formed with cooperating annular surfaces for clamping thediaphragm, said front cusing having an annular front wall formed with anapproximately central opening for the escape of the sound waves,arranged close to but normally out of contact with the central orvibratory portions of the diaphragni and forming therewith. an annularspace which at points adjacent the central opening thin as compared withthe radial width of the annulus, said opening having an internaldiameter not than one-third the diameter of the vibrating portion of thediaphragm, in combination with a resonator secured over said opening,said opening and the base of the resonator being circular andsubstantially concentric with the diaphragm whereby the peripheralboundary of said opening extends opposite substantially equivibratoryportions of said diaphragm, the resonator being vertically flared andlaterally fiattened toward its open end and terminating in an. oval bellmouth, one of said casings being provided with a bracket extendinglaterally thereof to a distance greater than the flattened side of themouth of the resonator and adapted to be secured to a vertical supportwith the major diameter of the resonator disposed vertically, to-

gether with means for applying power for forcibly vibrating saiddiaphragm by repeated forcible impacts displacing said diaphragm in adirection toward the front wall of the case, for the purpose described.

4:. A signal device comprising a vibratory diaphragm, a rear casing anda front casing formed with cooperating annular surfaces for clamping thediaphragm, said front casing having an annular front wall formed with anapproximately central opening for the escape of the sound waves,arranged close to but normally out of contact with the central orvibratory portions of the diaphragm and forming therewith an annularspace which at points adjacent the central opening is thin as comparedwith the radial width of the annulus, said opening having an internaldiameter not less than one-third the diameter of the vibrating portionof the diaphragm, in combination with a resonator secured over saidopening, said opening and the base of the resonator being circular andsubstantially concentric with the diaphragm whereby the peripheralboundary of said opening extends opposite substantially equivibratoryportions of said diaphragm, the resonator having its longitudinal axisstraight and perpendicular to the plane of the diaphragm and havingwalls vertically flared and laterally flattened toward its open end andterminating in an oval bell mouth, one of said casings being providedwith a bracket extending laterally thereof at right angles to both thelongitudinal axis and the major diameter of the resonator and to adistance greater than the flattened side of the mouth of the resonatorand adapted to be secured to a vertical support withthe major diameterof the resonator disposed vertically, said device being provided withvertically alined diametrically opposite exit openings communicatingrespectively with the upper and lower portions of the annular space infront of the diaphragm, for the purpose described.

A diaphragm horn comprising a vibratory diaphragm, means for applyingpower for forcibly vibrating said diaphragm to produce a definite noteof definite normally uniform frequency, a casing for the front of thediaphragm, having a front wall forming a space in front of saiddiaphragm, and formed with an opening for escape of the sound waves, incombination with a resonator secured over said opening, said opening andthe base of the resonator being circular and having an internal diameterapproximately one-third to two-thirds that of the vibratory portion ofthe diaphragm, the resonator being vertically flared and laterallyflattened toward its open end, and terminating in a bell mouth havingits lateral diameter less than its vertical diameter, and means forsecuring the device with the greater diameter of the resonatorsubstantially vertical.

6. A diaphragm horn comprising a vibratory diaphragm, means for applyingpower for forcibly vibrating said diaphragm to produce a definite noteof definite normally uniform frequency, a casing for the front of thediaphragm having a front wall approximately parallel with but spacedaway from the front face of said diaphragm to form a narrow annularchamber therebetween, and an approximately central opening for escape ofthe sound waves, in combination with a resonator secured over saidopening, said opening and the base of the resonator being circular andconcentrio with said diaphragm whereby the edges of said opening arelocated opposite substantially equivibratory portions of said diaphragm,and the resonator being laterally flattened toward its open end, andmeans for securing the device with the greater diameter of the resonatorsubstantially vertical.

7. A signal device comprising a resonator formed with a straight,relatively thick and short symmetrical laterally flattened body portionterminating in an oval bell mouth and means for supporting itapproximately parallel to the ground and with its major di ameterapproximately vertical, in combina tion with a diaphragm for excitingsaid resonator and means for applying power for forcibly vibrating saiddiaphragm to produce a definite note of definite normally uniformfrequency, for the purpose described.

8. A signaling apparatus adapted for use in exposed situations, saidapparatus comprising a vibratory diaphragm, means for repeatedlydisplacing the central portions of the diaphragm simultaneously in thesame direction, a substantially dust tight casing for the rear of saiddiaphra gm, said casing inclosing said displacing means, a front casingand attached mouth piece for the front of said diaphragm, said lattercasing being provided, with a pair of diametrically opposite exitopenings adjacent the periphery of the space between said diaphragm andsaid front casing, in combination with means whereby said signalingdevice may be secured to a support with either of said exit openings inthe lowermost position.

9. In a signaling instrument, the combination of a diaphragm, powerdriven means for vibrating said diaphragm, a two-part casing comprisinga rear section, and a front section, and clamping means for securing theperipheral portions of said diaphragm between the sections of saidcasing; a mouth piece connected with an approximately central openingthrough the front section of said casing; a plurality of exit openingsin the front section of said casing adjacent the peripheral portions ofthe cavity formed be tween said diaphragm and said front section of thecasing, but distributed in difierent portions circumferentially, so thatsaid instrument may be used in different positions with one or the otherof said exit openings in position to drain the lower portion of saidcavity in any of said positions.

10. In a signaling instrument, the combination of a diaphragm, poweroperated means for vibrating the same, a two-part casing comprising arear section, and a front section, and means for securing the peripheralportions of said diaphragm between the sections of said casing; a mouthpiece connected with an approximately central opening through the frontsection of said casing; a pair of diametrically opposite openingsadjacent the periphery of the space between said diaphragm and frontsection of the casing, so that said instrument may be used with eitherof said openings in position to permit expulsion of dirt, water, etc.,from the lower portion of said cavity when said diaphragm is vibrated.

11. A signaling apparatus comprising a vibratory diaphragm, power drivenmeans for vibrating the same, and a casing co1nprising a rear sectionand a front section, provided with a mouth piece, said diaphragm beingclamped between said sections, one section of said casing being providedwith a laterally extending member adapted to be rigidly secured to avertical support; the front section of said casing being provided withholes at opposite points adjacent the clamped surfaces of the diaphragm,so that at least one of said holes is presented adjacent the lowerportion of the space between the diaphragm and the front sect-ion of thecase, whichever side of said device is lowermost when the device issecured in operative position by said laterally extending support.

12. A diaphragm actuated horn, comprising a diaphragm, means foractuating the same, and means for securing the device with the diaphragmin an approximately vertical position, in combination with a casing forthe air vibrating face of said diaphragm, a resonator secured over anopening in said casing, said resonator being laterally fiattenedadjacent the open end thereof, so that its major cross-sectionaldiameter lies in a vertical plane, the said front casing being providedwith exit openings adjacent the top and bottom thereof, whereby one ofsaid exit openings will be presented at the lower portion of the cavityin front of the dia phragm, whichever side up the flattened horn may besecured.

13. In a signaling apparatus, a device comprising a casing having afront wall, and having a laterally extending support member, and adiaphragm and actuating means therefor within said casing, saiddiaphragm being clamped within said casing near to but spaced away fromsaid front wall and said front wall being provided with holes atopposite points adjacent the clamped surfaces of the diaphragm so thatat least one of said holes is presented adjacent the lower portion ofthe space between said diaphragm and said front wall whichever side ofsaid device is lowermost when the device is secured in operativeposition by said laterally extending support member.

Signed at New York city, in the county and State of New York, thisfourth day of May, A. D. 1909.

MILLER REESE HUTCHISON.

Witnesses:

GEORGE C. DEAN, IRVING M. OBRIEGHT.

